<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="lib/vue.js"></script>
</head>
<body>
<button onclick="fn()">点我</button>
<div id="root">
    <p>{{a}}</p>
    <p>{{b}}</p>
    <p>{{c}}</p>
    <p>{{d}}</p>
</div>
</body>
<script>
    const data = {
		a:1,
		b:2,
		c:3,
		d:4
	}
	const vm = new Vue({
		el: "#root",
        data
	});
	console.log(vm.$data === data);// true
    function fn(){
		vm.$data.a = 100;
    }
</script>
</html>